Success breeds imitation breeds competition, and Whole Foods is feeling the heat: its stock dropped more than 20 percent on news of slowing sales.

Said CEO John Mackey on his blog:

There has been an explosion in interest from our supermarket competitors in virtually everything we are doing, from copying many aspects in the design of our stores to selling more organic foods of all types, other supermarkets are studying and emulating us in dozens of different ways in their attempt to compete more aggressively against us.

Ouch! After it announced the sales slowdown Thursday, the company’s stock took its biggest dive in nearly eight years. Apparently companies like Trader Joe’s and Wegmans (an East Coast retailer) are closing in on its territory and conventional supermarkets are snipping at its heels.

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WFM responded by upping the salaries of its top execs to prevent them from jumping ship to competitors. Mackey took the high road and slashed his own salary to just $1.